LIVE animals are increasingly being experimented on by Irish scientists, despite controversy over the practice.
Figures obtained by the Irish Independent show researchers in Trinity College spent more than €368,000 on live animals in only 12 months to use in tests aimed at treating disease in humans.
The figure is more than double what was spent the previous year.
Dogs, pigs, rabbits, mice and rats have been used in the university's medical experiments, but there is pressure from the EU to find other ways of conducting tests.
The Trinity figures show the huge cost of "maintenance and welfare" during the same period, bringing the bill to €665,102.
Between October 2011 and last September the university bought 15 pigs, 20,094 mice and 6,579 rats for use in its labs.
The animals are tested as part of the exploration of treatments for diseases such as Alzheimer's, arthritis, multiple sclerosis, schizophrenia and genetic disorders.
The university said any research carried out on animals requires the prior licensing of the person and the project by the Minister for Health Dr James Reilly.
A Trinity spokesman said all animal experimentation applications are "ethically reviewed" by its Animal Research Committee which ensures whether there is is legitimate "scientific justification" for the proposed work.
However, the Irish Anti-Vivisection Society, which is campaigning for an end to the use of live animals, argues that animal experimentation "allows the infliction of pain and suffering".
They fear that animals are placed under undue pain and distress in the name of science, and insist that it is still too easy to resort to using live creatures when alternative means of experimentation should be explored.
From January 1, the EU Directive will mean alternative testing methods should be used if they can produce equally valid results.
The Department of Health said that while it is desirable to replace the use of animals in scientific procedures, these tests continue to be necessary.